Oil flow switch having pivoted cupshaped actuator



March 8, 1966 B. H. CLASON 3,239,622

OIL FLOW SWITCH HAVING PIVOTED CUP-SHAPED ACTUATOR Filed Aug. 9, 1963 wgm j l f T 1. 7 0,, a"; 1 I /j; INVENTOR. i Bari/'1 )2. 670.9021

L BY I H (L QQW 1 l H18 ATTORNEY United States Patent 3,239,622 OIL FLOWSWITCH HAVING PIVOTED CUP- SHAPED ACTUATOR Ber-til H. Clason, Flint,Mich., assignor to General Motors Corporation, Detroit, Mich., acorporation of Delaware Filed Aug. 9, 1963, Ser. No. 300,975 7 Claims.(Cl. 20081.9)

This invnetion relates to electrical switches and more particularly toan electrical switch which is responsive to fluid flow.

It is an object of the present invention to provide an electrical switchthat, when combined with an indicating circuit, will notify a driver ofa flow condition in his oil system.

It is a further object of the present invention to provide a switchwhich can be submerged in a fluid whose flow is being monitored.

It is still a further object of the present invention to provide asimple flow responsive electric switch with a minimum number of movingparts.

It is yet a further object of the present invention to provide a switchthat can be easily mounted in a variety of locations in an oil system.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred embodiment of the present invention isclearly shown.

In the drawing:

The single figure drawing is a sectional view of a switch made inaccordance with this invention illustrated controlling a typical warningtype of electrical circuit.

Referring now to the drawing, a terminal 10 is mounted in a terminalholder 12 composed of any well-known insulating material. The terminalholder is firmly engaged with a metallic switch body 14 by being lodgedbetween a surface 16 of the switch body 14 and a rolledover flange 18 ofthe switch body 14. The terminal 10 has a portion extending into theswitch body forming a contact 20. On the opposite end of the switch bodyfrom the terminal entry point is an aperture 22 through which a contactpin 24 is slidably disposed. The contact pin 24 has a retaining ring 26,said retaining ring having chamfered portion 28. One end of the contactpin 24 has a contact head 30, said contact head having an abutment 32serving to retain a spring 34 in biased engagement with the contact head30 and a wall portion 36 of the switch body 14. A substantiallycup-shaped actuator 38 is biasedly held between a wall portion 40 of theswitch body 14 and one surface of the retaining ring 26. The switch body14 has a threaded portion 42 disposed to engage a threaded opening 44 ofa fluid carrying container 46. The switch body 14 has an area 48 withflats thereon to facilitate the mounting of said switch to a threadedopening in a container.

In operation, the switch or the terminal 10 is connected in series witha tell tale light 50, an ignition switch 52 and a power source 54 toform an indicating circuit, the switch body being grounded as is oneside of the power source.

The switch body 14 can be mounted in any convenient location in an oilsystem of an atuomobile. A pipe thread connection is established througha drilled and tapped hole in the oil system in a manner that will allowthe connection to withstand up to 150 pounds per square inch of oilpressure at a temperature of from -60 to +300 F. without leaking. Withthe ignition switch 52 in the ON position and no oil flow beinggenerated in the oil system, a circuit will be established in theaforementioned indicating circuit. With the ignition switch in the3,239,622 Patented Mar. 8, 1966 ice closed position and the enginestarted, oil pressure would normally cause an oil flow through oilpassage and past the cup-shaped actuator 38, extending into the oilpassage, to cause the breaking of the established circuit. This isbrought about by a movement of the oil in the passage 60 pushing againstany side of the cup-shaped actuator 38, whereby the contact head 30 islevered out of its biased engagement with the contact 20 by an edge ofthe cup 38 pivoting on surface 40 of the body 14. More specifically,this is accomplished by the cup-shaped actuator being pushed in onedirection and drawing its inside surface down against the chamferedportion 28 of the contact pin 24 as the actuator pivots on one of itsedges. The contact pin 24 being loosely, slidably engaged with theaperture 22 is easily drawn away from the contact 20 thereby breakingthe circuit therethrough.

The only metal to metal contact in this device is between the contactpin 24 and the body 14 and between the contact pin and the cup-shapedactuator 38. In view of the loose fit of the contact pin 24 within theaperture 22, the oil being monitored can easily pass into the switchbody through aperture 22 causing the aforementioned parts to beconstantly lubricated.

Another advantage of this invention is that the actuator is responsiveto flow against any side and so the mounting in the threaded part issimplified somewhat. Vane type flow switches require perpendicularalignment of the vane with the fluid passage.

The utility of this invention is apparent in that it enables theoperator of a vehicle to be aware, through a medium of a tell tale lampmounted in the driver compartment, of the actual flow of oil in theengine oil system. It is possible in automobile engines of present daydesign to have an oil pump creating an oil pressure but, due to ablocked oil passage, to have no oil actually flowing in the oil system.An example of this situation is illustrated in the simple oil system inthe drawing. A pump 56 of an engine 58 draws oil from a sump orcrankcase 61 and moves the oil through a filter 62. If the filter 62 isblocked with engine sludge, no flow will occur in the engine but thepump 56 will continue to operate and pressure indications will remain atthe pump outlet. Therefore, it is apparent that destructive engine wearcould result due to no oil flow while a pressure gauge registered normalpressure. This invention is meant to obviate this problem.

While the embodiment of the present invention, as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. An electrical switch comprising a body, an insulated conductive meansextending through a wall of said body, a contact means extending throughanother wall of said body disposed in biased engagement with saidinsulated conductive means forming part of an electrioal circuit, and anactuator means including flow responsive means carried by said cont-actmeans, said actuator means being responsive to fluid flow whereby saidconductive means and contact means are disengaged to break theelectrical circuit.

2. An electrical switch comprising a conductive path, said pathincluding a conductive means and a contact means, said conductive meansdisposed in biased engagement with said contact means, said contactmeans having an extension carrying flow responsive means adapted to besuspended in -a fluid passage, said flow responsive means beingresponsive to fluid flow in the passage to bring about an interruptionin said conductive path.

3. An electrical switch comprising a body having a fluid passage and acompartment therein in fluid communication therewith, a first conductiveelement being insulated from said body and extending into saidcompartment, a second conductive element extending through a wall ofsaid body and being disposed in biased engagement with said firstconductive element, said second conductive element having a pivotableetension protruding into a fiuid passage, said extension beingrcsponsive to fluid flow in said passage to draw said second conductiveelement away from said first conductive element.

4. An electrical switch for an oil flow indicating system comprising abody with a compartment therein, an external terminal extending througha wall of the body into said compartment forming a first contacttherein, a pin contact being in biased engagement with said firstcontact, said pin contact having an extension through a wall of saidcompartment in opposed relations-hip to the entry point of said externalterminal, said extension carrying a cup-shaped member in looseengagement therewith whereby a flow of oil in said oil flow indicatingsystem breaks the biased engagement of said first contact and said pincontact by exerting pressure on the cup-shaped member thereby causing abreak in the indicating circuit.

5. In combination, an engine oil system, a condition indicating means,and an electrical switch controlling said condition indicating means,said switch comprising a body having apertures in two walls thereof, aterminal pin having a contact formed on one end thereof beinginsulatedly mounted in one of said apertures, a contact pin slidablydisposed in another of said apertures having one end in biasedengagement with said terminal pin cont-act, and flow responsive meansprojecting into said oil system having a flat plate area attached to asecond end of said contact and adapted to be moved when any flow occursin the oil system thereby levering said contact pin out of biasedengagement with said terminal contacts causing a change in saidcondition indicating system.

6. An oil flow switch comprising a body adapted to be inserted into anaperture in an oil system, said body having apertures in opposed ends,one of said apertures being adapted to receive and be sealed by aninsulated terminal pin, said terminal pin being a conductive path for anindicating circuit and having a contact portion on the inside of saidbody, a pin disposed in sliding relationship with another of saidopposed apertures, said pin having a contact being kept in biasedengagement with said terminal contact on one end, said terminal contactand said pin contact closing an electrical circuit when engaged, saidpin having an actuator end and extending through said opposed aperture,and an actuator member being loosely carried by said actuator end andhaving sufiicient flat plate area in the oil system to cause aresistance to flow therein, said actuator being pivotable on the base ofsaid body during a flow of oil in the system thereby drawing said pinthrough said opposed aperture and causing a separation of said terminalcontact and said pin contact breaking the circuit therethrough.

7. A flow switch for nonconductive fluids comprising a housing, aplurality of contact means within said housing operable to close anelectrical circuit therethrough, one of said contact means being fixedand another of said contact means being in biased and opposedjuxtaposition to said fixed contact means, said biased contact meanscarrying a lever means, said lever means and said plurality of contactmeans being disposed in a fluid passage and being responsive to fluidflow in said passage to lever said biased contact away from said fixedcontact means thereby breaking said electrical circuit.

References Cited by the Examiner UNITED STATES PATENTS 852,979 5/1907Rice ZOO-81.9 1,856,584 5/1932 Parkhill ZOO-81.9 2,166,264 7/1939 Piper20( 81.9 2,879,892 4/1959 Frakes 200-81.9 X

BERNARD A. GILHEANY, Primary Examiner.

1. AN ELECTRICAL SWITCH COMPRISING A BODY, AN INSULATED CONDUCTIVE MEANSEXTENDING THROUGH A WALL OF SAID BODY, A CONTACT MEANS EXTENDING THROUGHANOTHER WALL OF SAID BODY DISPOSED IN BIASED ENGAGEMENT WITH SAIDINSULATED CONDUCTIVE MEANS FORMING PART OF AN ELECTRICAL CIRCUIT, AND ANACTUATOR MEANS INCLUDING FLOW RE-